This invention relates generally to slide fasteners, and more specifically to the improved construction of a stringer for slide fasteners of the type having a row of discrete fastener elements of substantially U-shaped configuration affixed to one of the longitudinal edges of a stringer tape for mating interengagement with identical fastener elements of a companion stringer.
There has been known a stringer construction for the slide fasteners of the type above defined wherein those ends of a pair of legs or shanks of each fastener element remote from its coupling head are so deformed as to provide guideways for the marginal guide flanges of a slider traveling along rows of such interlockable fastener elements. While the movement of the slider along the fastener elements is certainly made smoother thanks to this known stringer construction, the stepped configuration of the legs of each fastener element necessitates a significantly increased dimension for the fastener element in a direction perpendicular to the plane of the stringer tape. Such "thick" fastener elements are of course aesthetically unappealing.
If this disadvantage is circumvented by lessening the thickness of the fastener elements, then the steps between the deformed end portions of the legs of each element and their remaining portions must correspondingly be decreased in height. The steps of such decreased height may become unable to definitely engage the marginal guide flanges of the slider from within the slider body, so that the slider will tend to come off the rows of fastener elements whenever lateral pulling forces are exerted from both sides of the slide fastener during or after the fastener closing movement of the slider.